Homer <usenet@xxxxxxxxxx> espoused:
> Verily I say unto thee, that Mark Kent spake thusly:
>> Homer <usenet@xxxxxxxxxx> espoused:
>>> Theoretically one could bond 24 64Kb ISDN channels to achieve
>>> 1.5Mb/s the really hard (and expensive) way, I suppose. Also I
>>> believe that each line only supports 128k ISDN2e, so he'd need to
>>> have 12 phone lines too. In UK (BT) price terms, that's 12 line
>>> rentals @ £10.50/month, plus 12 ISDN2e subs @ £97.47/quarter, plus
>>> the cost of calls (no flat rate like ADSL), plus VAT @ 17.5%.
>>> That's £7,273.91/year ($13,573.21) including VAT, but excluding the
>>> cost of calls, which according to my experience might easily be
>>> around £1000.00/quarter for a heavily used line, giving a
>>> conservative rounded total of around 10 grand UK (20 grand US) a
>> Why on earth would you do it that way...
> Well of course I wouldn't, it's purely hypothetical :)
> Also, I note I've /underestimated/ the call charges, since that's £1000
> per quarter per /line/ ... I've only accounted for /one/ line, not all
> 12, so the actual final total would be over 55 *grand*. Double ouch!
Well, yeah, but you just wouldn't do it that way.
>> Even if you wanted a lot of lines as individual ISDN lines, surely
>> you'd go for ISDN30, so you have only one access line?
> Ah OK, I hadn't heard of that before. The last time I used ISDN it was a
> residential product nicknamed Home Highway (roughly comparable to ISDN2e).
Home Highway was a precursor to ADSL in many respects, using derived
circuits over copper pair. It had a fairly short lifetime.
>> and I see that ISDN30 rental starts at £54.57 + vat for rental, per
>> quarter. All BT's prices are up on its website (ofcom requirement)
>> for services where BT has "significant market power", so you don't
>> need to guess, you can just look them up. In any case, that means
>> that the rental figure you quote above is, by my quick calculation,
>> around £6,000 per year too high.
> This is where I obtained the prices for ISDN2e:
> I'm not sure why ISDN30 is cheaper.
I think you need to pick the right things... :-)
>> ISDN call charges, again according to the price list, range from 0.85
>> pence per minute for weekend off peak up to 7.9ppm for national peak
>> rate. To get £1,000 per quarter in call charges, you'd need to be
>> making 12,600 minutes of calls per quarter, all in peak time, or
>> almost 27 days of constant peak-time calling, to national numbers, to
>> get there.
> At the time I was using the Home Highway product, I was using it pretty
> much the same way I use ADSL now (always-on), which means 24 hours/day
> background activity from the server for things like rsync (mirroring),
> as well as normal usage, so each quarter I was essentially making ~90
> days of constant calls 24 hours/day on two lines (channel bonded ISDN)
> to an 0845 or so-called "lo-call" number, which was also my "Friends and
> Family" so-called "Best Friend" number. Even including the fact that it
> was discounted for being both an 0845 and a "Best Friend" number, my
> call charges came to ~£1000 per quarter. I had that service for approx 2
> years before ADSL finally came to town.
> Ultimately there may have been a cheaper alternative at the time, but
> not one for residential customers AFAIK. If I'd been made aware of such
> a product than I certainly would have jumped at the chance to save £1000
> per quarter.
Call charges have been falling for as long as I recall. If you were
using Home Highway, it would've been some years ago. Pricing is quite
I really am not familiar enough with product pricing to tell you what
might or might not have been less expensive at that time.
>> If you're really making that many calls *to the same number*, then
>> it's most likely that some kind of leased line solution will be much
>> less expensive, as your're just tieing up the switched network all
>> day, every day.
> I seem to recall investigating leased lines at the time, but all of the
> products I looked at were in the 10K bracket, and were all oriented to
> business use.
10kpa or 10kpcm? If it's 10kpa, then it's less expensive?
>> If this is for internet dial-up, then I would think that you'd be
>> getting a local rate, which would be much less expensive, but I don't
>> know for sure.
> Yes it was 0845 "lo-call" rates, which I believe lies somewhere in
> between local and national.
0845 is a mercury numbering range, not a BT one, I've no idea what they
>>> Our 21CN PSTN switchover target is supposed to be Q3 2011. Until
>>> then I'll have to "make do" with 8Mb/s.
>> You can always have an additional ADSL line, if you need additional
> ATM it's not really an issue, since I sync at 8Mb and get a steady 6.5Mb
> on most days (Entanet). The cost of a second line doesn't really appeal
> to me either :( Although 16Mb bonded does sound nice in theory.
That's a good rate, better than I get here, to be honest :-)
>> One thing to consider, of course, with ADSL, is the contention rate.
>> You don't actually get 8Mbit/s, constantly, guaranteed to any
>> destination, what you actually get is up to 8Mbit/s of access into
>> the wider internet, shared with probably up to 30 other users, who
>> might also want the same access rates... the whole thing works on
>> the assumption that consumption of IP networks is, well,
>> statistically muxable. Of course, this only works to a point, as
>> like in the case of the PSTN, we get busy-hours.
> My exchange covers 3 houses and a post office (OK, that's a /slight/
> underestimation), so the contention round these parts is pretty low :)
In which case, you're pretty well off, I'd say.
>> For ADSL2+, the maximum rate should rise up to 24Mbit/s, but
>> obviously this will depend on normal transmission line issues,
>> including length of the line, condition of the line and so on. You
>> canna change the laws of physics.
> You misspelled "cannae", Scotty :)
> (As in "Ye cannae shove yer grannie aff the bus".)
My fault for using foreign languages, I suppose :-) In yorks, nay is
spelt nay :-)
> Personally I'm rather apprehensive about 21CN, in much the same way as I
> was about the probability of being LLU'ed without warning by my ISP, and
> ending up on a dog-slow Datastream rather than my current BT-managed
> IPStream. Indeed this is one of the main reasons I migrated recently,
> along with my overall distaste for the company that assimilated the ISP
> I was with (Tiscali bought Nildram). WRT 21CN, I simply don't know much
> about it at all, so I'll reserve judgement until the reports start
> flooding in.
Time will tell, I'm sure.
>> The presently mooted plan to do fibre to the kerb (see recent news)
>> could bring as much as 100Mbit/s to every house, but again, you'd
>> need to look at contention ratios and the economics of the whole
>> thing - it doesn't come free.
> Oh I'm more than happy to pay for a good service (£1000 per quarter,
> remember), but something tells me it'll be a /very/ long time before my
> muddy backwater sees 100Mb ... or even 24Mb. Right now I'm happy enough
> on 8Mb.
It'll be a long time generally. The UK has around 28 million lines of
copper. Replacing 28,000,000 lines with something else is no small
>> On ISDN30 connections, each timeslot (64kbit/s channel) is guaranteed
>> to take the same route on any call either nationally or
>> internationally so that any bonding equipment in use can assume that
>> bits sent in order will arrive in order at the distant end.
>> Furthermore, the calls are guaranteed to meet G.114 delay
>> requirements, ie., not exceed 400ms round-trip delay to any
>> destination, with error performance meeting G.826, and maintenance to
>> M.2101 parts 1 and 2.
> Interesting; thanks for the explanation. So why is ISDN2e more expensive
> then, is it because it's a legacy product that takes additional support?
I don't know anything about pricing, sorry. If you contact BT, I'm sure
one of the sales people will tell you, though.
>> Now, if you want some *serious* bandwidth, you could take a look at
> 2.5Gb! Holy crap, that's faster than the central pipes!
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